A Seattle woman died from a brain-eating amoeba after she ran tap water through her Neti pot.

The woman, 69, saw a specialist for a recurring sinus infection and was told to try running saline through her sinuses. Instead of using sterilized water or saline, she used tap water filtered with a Brita purifier.

Doctors say that is likely how she contracted a Balamuthia mandrillaris, an amoeba found in soil and fresh water that can cause an infection of the central nervous system.

Nasal irrigation, where someone tries to flush their nasal cavity to rid it of mucus, has been linked to the contraction of another potentially fatal amoeba, which led doctors to make the connection.

Both are extremely rare.

The report, published in the International Journal of Infectious Diseases, said it could happen to others. The authors recommend doctors consider checking for these amoebas when patients show up with a persistent nasal sore.

The woman was diagnosed several times with rosacea when a sore appeared on her nose. After a year and several rounds of medication that didn’t cure the sore, the woman experienced a seizure.

While she was in the hospital, a brain scan revealed she had a brain lesion.

Doctors originally thought it might be related to her history of breast cancer. A biopsy showed that it didn’t line up with the usual route that breast cancer patients might experience seizures.

The woman continued to have seizures, partial paralysis, arm and leg numbness and an altered mental state for the next few weeks.

Tests showed that her brain lesion had grown in size and number. Finally, a doctor at Johns Hopkins University suggested she might be infected with an amoeba. By then, it appeared to be too late.

Doctors gave her anti-amoeba medications and worked with the federal Centers for Disease Control and Prevention, but a week later, she had become comatose, and her family decided to take her off life support.

The report notes that anyone who does not use saline in a Neti pot or other method of nasal irrigation could be at risk for a similar amoeba.

If caught early enough, some people have survived. However, most often, the infection is deadly.